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New to the forum. I have a question about cooling hose routing, I just got a boat(2003 4.3 V-6) that hasn't run in two years. Trying to get it running to see what I got. The hoses were disconnected from the sea pump. Owner didn't know which one was which. Which hose is the inlet from lower unit lake water and which hose is the outlet that goes to the thermostat housing. Sorry for hijacking a photo from PDACPA but I didn't have a good one and it is exactly what I am looking at.Thanks for any advice.

I have a 2003 4.3 VP also. The top hose should be the inlet hose routing up from the back of the boat. If you have the engine flush adapter (garden hose with blue cap) then the hose from the flush adapter port tees into the inlet hose also.

The bottom hose should be the output and routes up to the thermostat on the top of the engine.

If unsure, bump your engine over a partial turn (don't let it start up) and note which way it turns. The impeller spins the same direction as the engine and impeller should always turns AWAY from the inlet tube and TOWARDS the outlet tube.

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2003 FW 170 Freedom 4.3 GL/SX

On a standard rotation engine, the top hose is the Inlet, and the bottom goes to the thermostat housing.

The engine shown in this photo has the infamous "Duct Tape Replacement for P/N 3857954 Stop Lug"

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"Knot Easy" 2000 Horizon 240 Volvo 5.7GS /SX
tow: 2017 Honda PILOT EXL-AWD
prev. boats:
'87 Chaparral 198CXL 4.3 OMC Cobra
'69 Jetstar 16ft Ski Boat, 115hp Yamaha
'68 Aluminum Jon Boat, 3hp Sears
'64 Water Wings

Thanks a ton guys. Top hose inlet , bottom hose to thermostat. Got it. I think the previous owner hooked it up backwards. Impeller looks great as I know it was recently replaced. As for the duct tape, my rubber bumper is disintegrated, I am using a short piece of 3/4" auto heater hose and it seems to fit great. Both exhaust manifolds cracked, previous owner only drained the block for winter not the manifolds. That's how I acquired it. I have an older Mercruiser so working on this Volvo is new. Now just hoping the block isn't cracked, so far so good, it holds water. Putting on new manifolds next week to try and run.